While Las Vegas is a major hotspot for tourists and a must-visit when in the USA, given its sunny and dry weather that lasts almost all year round, the best time to visit Vegas is during its less hot months of October through March. The weather during these months is cold, dry and the least humid. The average temperature during these months ranges from 8? to 23?. The hottest months of Las Vegas are from May through August, with negligible precipitation but very low humidity, owing to its subtropical hot desert climate. Because of its climatic condition, Las Vegas has a long and intensely hot summer season, and a shorter but cooler winter season, and intermittent rains throughout the year, with an annual 21 rainy days on average.